Semiconductor devices are used in a large number of electronic devices, such as computers, cell phones, and others. Semiconductor devices comprise integrated circuits that are formed on semiconductor wafers by depositing many types of thin films of material over the semiconductor wafers, and patterning the thin films of material to form the integrated circuits.
One of the goals of the semiconductor industry is to continue shrinking the size and increasing the speed of individual devices. However, isolating devices with 28 nm transistor nodes, 20 nm transistor nodes, and nodes beyond has presented challenges. For example, metal gap filling becomes increasingly difficult as the node size decreases.
In addition, the processes used to form sub 28 nm transistor nodes may undesirably damage, for example, a low-k dielectric material incorporated in the device. Furthermore, the processes may also negatively impact wafer acceptance test (WAT) yield and reliability results.
Corresponding numerals and symbols in the different figures generally refer to corresponding parts unless otherwise indicated. The figures are drawn to clearly illustrate the relevant aspects of the embodiments and are not necessarily drawn to scale.